Conventional and New Processes for Urban Wastewater Disinfection: Effect on Emerging and Resistant Microorganisms

The continuous release of chemical and microbiological pollutants into the environment and the increasing demand for safe water call for effective water and wastewater treatment processes. In particular, the detection of resistant microorganisms (e.g. antibiotic-resistant bacteria) in the effluents of urban wastewater treatment plants disposed into surface water or reused (e.g. in crop irrigation) shows that conventional treatments and disinfection processes do not effectively control the spread of pathogens into the environment. There is a need for new and more effective disinfection processes and technologies. The aim of this chapter is to briefly describe some of the emerging and antimicrobial-resistant microorganisms detected in wastewater, as well as the conventional and new advanced available technologies for wastewater disinfection, and to evaluate and discuss their effect on these microorganisms. Moreover, regulations and policies on wastewater reuse are also critically discussed and compared.